Water flowing in channels through caves, caverns, and larger galleries in karst terranes [20]. Synonyms: (French.) riviere souterraine; (German.) Hohlenflu., unterirdischer Flu.; (Greek.) ypoghios roe, potamos; (Italian.) fiume sotterraneo; (Russian.) podzemnaja reka; (Spanish.) rio subterraneo; (Turkish.) yeralti nehri, deresi; (Yugoslavian.) podzemni tok, podzemna rijka, podzemna reka. See subterranean river.